| Abbreviation | Definition |
|---|---|
| OWSE | Operational World Weather Watch Systems Evaluation |
| OWW | One-Wire Weather |
| P | Precipitation |
| P3I | Preplanned Product Improvement |
| PA | Pressure in the Atmosphere |
| PAC | Potentiometric Analysis Collection |
| PACS | Pan- American Climate Studies |
| PACS | Polar Acquisition and Control Subsystem |
| PAGASA | Philippine Atmospheric, Geophysical, and Astronomical Services Administration |
| PAL | Present Atmospheric Level |
| PAW | PDA Animated Weather |
| PAWS | Plants, Animals, Water, and Soil |
| PB | Pilot Balloon |
| PC | Physical Characteristics |
| PC | Program Council |
| PCC | Project Climate Conditions |
| PCGRAFAX | PC-based High Frequency Facsimile System |
| PCIS | Pacific Climate Information System |
| PD | Project Director |
| PDM | Physical and Dynamic Meteorology |